Quarterly Report for Quarter Ending September 30, 2025 (Form 10-Q)

Management's Discussion and Analysis of Financial Condition and Results of Operations

The following discussion contains forward-looking statements that involve risks and uncertainties. Our actual results could differ materially from those discussed here. Factors that could cause or contribute to such differences include, but are not limited to those discussed in this section as well as factors described in Part II, Item 1A "Risk Factors."

Overview

Strategic Direction of Our Business

Nektar Therapeutics is a clinical stage, research-based drug discovery biopharmaceutical company focused on discovering and developing innovative medicines in the field of immunotherapy. Within this growing field, we direct our efforts toward creating new immunomodulatory agents that selectively induce, amplify, attenuate or prevent immune responses in order to achieve desired therapeutic outcomes. We apply our deep understanding of immunology to identify and create innovative drug candidates and use our drug development expertise to advance these molecules through preclinical and clinical development. Our pipeline of clinical-stage and preclinical-stage immunomodulatory agents targets the treatment of autoimmune diseases (e.g. rezpegaldesleukin and NKTR-0165, respectively) and cancer (e.g. NKTR-255). We continue to make significant investments in building and advancing our pipeline of drug candidates as we believe that this is the best strategy to build long-term shareholder value.

Autoimmune and inflammatory diseases cause the immune system to mistakenly attack and damage healthy cells in a person's body. A failure of the body's self-tolerance mechanisms enables the formation of the pathogenic T lymphocytes that conduct this attack. Our drug candidate rezpegaldesleukin is a potential first-in-class resolution therapeutic that may address this underlying immune system imbalance in people with autoimmune disorders and inflammatory diseases. It is designed to target the interleukin-2 (IL-2) receptor complex in the body in order to stimulate proliferation of powerful inhibitory immune cells known as regulatory T cells (Treg cells). Describing the critical role of Treg cells in maintaining balance in the immune system earned Drs. Mary E. Brunkow, Fred Ramsdell and Shimon Sakaguchi, the Nobel Prize in medicine on October 6, 2025. By activating these Treg cells, rezpegaldesleukin may act to bring the immune system back into balance. Rezpegaldesleukin is being developed as a once or twice monthly self-administered injection for a number of autoimmune disorders and inflammatory diseases.

In October 2023, we initiated a Phase 2b clinical study of rezpegaldesleukin in patients with moderate-to-severe atopic dermatitis (the Phase 2b RESOLVE-AD trial). On February 11, 2025, we announced that the FDA had granted Fast Track designation for rezpegaldesleukin for the treatment of adult and pediatric patients 12 years of age and older with moderate-to-severe atopic dermatitis whose disease is not adequately controlled with topical prescription therapies or when those therapies are not advisable. In March 2024, we initiated a Phase 2b clinical study in patients with severe-to-very severe alopecia areata (the Phase 2b RESOLVE-AA trial). On July 29, 2025, we announced that the FDA had granted Fast Track designation for rezpegaldesleukin for the treatment of severe-to-very severe alopecia areata in adult and pediatric patients 12 years of age and older who weigh at least 40 kg. On February 24, 2025, we announced that we had entered into a collaboration agreement with TrialNet to evaluate rezpegaldesleukin in patients with new onset stage 3 type 1 diabetes mellitus in a Phase 2 study. TrialNet will conduct the study with funding from the National Institutes of Health, primarily through the Special Statutory Funding Program for Type 1 Diabetes through the National Institute of Diabetes and Digestive and Kidney Diseases. Nektar will supply rezpegaldesleukin for the study and will retain all rights to the rezpegaldesleukin program under the collaboration.

On June 24, 2025, we announced statistically significant data from the 16-week induction period of the ongoing Phase 2b REZOLVE-AD trial being conducted in 393 patients. In the trial, patients were randomized (3:3:3:2) to receive subcutaneous treatment with one of three doses of rezpegaldesleukin: a high dose of 24 µg/kg every two weeks (q2w), a middle dose of 18 µg/kg every two weeks (q2w), and a low dose of 24 µg/kg every four weeks (q4w), or placebo q2w. The primary endpoint and secondary endpoints were assessed at week 16. Following the 16-week induction period, rezpegaldesleukin-treated patients who achieved Eczema Area and Severity Score (EASI) percent score reductions of >50 were re-randomized (1:1) to continue at the same dose level on a q4w or q12w regimen through week 52 in a blinded maintenance period. Placebo patients with EASI percent score reductions of >50 percent continue to receive placebo q4w.

As announced on June 24, 2025, the Phase 2b REZOLVE-AD trial met its primary endpoint of the mean improvement in EASI from baseline at week 16 for all three dose arms of rezpegaldesleukin versus placebo (p<0.001). All three dose arms also achieved statistical significance at week 16 for the key secondary endpoints of EASI-75 (percent of patients who achieve ≥75% reduction in EASI from baseline), EASI-50 (percent of patients who achieve ≥50% reduction in EASI from baseline) and BSA (mean percent improvement in Body Surface Area score from baseline). The q2w arms of rezpegaldesleukin (high and middle doses) achieved statistical significance at week 16 for the key secondary endpoints of vIGA-AD 0/1 (percent of patients achieving a score of 0 or 1 on the validated Investigator's Global Assessment for Atopic Dermatitis with ≥ 2-point reduction from baseline) and Itch NRS (percent of patients with baseline ≥ 4 who experienced a ≥ 4-point reduction in the Itch Numerical Rating Score from baseline). In addition, at week 16, the high dose of 24 µg/kg q2w achieved statistical significance on EASI-90 (percent of patients who achieve ≥ 90% reduction in EASI from baseline). When evaluating EASI-75 and EASI-90 by disease severity using baseline vIGA-AD score, similar responses were observed in severe patients (baseline vIGA-AD of 4) as in moderate patients (baseline vIGA-AD of 3).

In addition, the safety profile for the 16-week induction period for rezpegaldesleukin in the Phase 2b REZOLVE-AD trial was consistent with previously reported results. The most common treatment-emergent adverse events (TEAEs) were local injection site reactions (ISRs), observed in 69.7% of all rezpegaldesleukin-treated patients, with the largest proportion of these being mild or moderate (99.6%). ISRs were self-resolving and <1% of patients discontinued because of an ISR. Across all rezpegaldesleukin doses administered in the study over the 16-week induction period, 55.9% had no reports of ISRs, 30.1% had mild reports, 13.8% had moderate reports, and only 0.2% were severe. Other TEAEs more commonly observed (>5%) in the study treatment arms (n=320) versus placebo (n=73) include eosinophilia (7.8% vs. 2.7%), pyrexia (6.3% vs 2.7%), headache (6.3% vs. 4.1%) and arthralgia (5.0% vs 1.4%). In the pooled rezpegaldesleukin arms, TEAEs, excluding ISRs, were reported in 60.3% of patients and in 57.5% of placebo-treated patients. There was no increased risk of conjunctivitis, oral ulcers, or infections, including oral herpes, in the rezpegaldesleukin arms.

On September 18, 2025, we presented new data from the Phase 2b REZOLVE-AD trial at the European Academy of Dermatology and Venereology (EADV) 2025 Congress. Building on previously presented data, these data demonstrated that high dose rezpegaldesleukin achieved statistical significance on multiple patient-reported outcome assessments at completion of the 16-week induction period. Additionally, as observed interim data for patients who previously received placebo during the induction period and crossed over to receive 24 weeks of treatment with high dose rezpegaldesleukin had increased EASI-75 and vIGA-AD efficacy with extended dosing beyond week 16.

We remain on track for a topline data readout from the Phase 2b RESOLVE-AA study in December 2025.

We continue to advance our most promising research drug candidates into preclinical development with the objective of advancing these early-stage research programs to human clinical studies over the next several years. Our lead research program is based on tumor necrosis factor (TNF) receptor type II (TNFR2) agonism, without modulation of the TNFR1 signaling, after we exercised an option in December 2023 to gain an exclusive license to specified agonistic antibodies and other materials that were developed pursuant to a research collaboration and license option agreement we entered into with Biolojic Design, Ltd. in 2021. TNFR2 signaling drives immunoregulatory function and can provide a direct protective effect for tissue cells. TNFR2 is highly expressed on Tregs, neuronal cells and endothelial cells and has been shown to potentiate the suppressive effects and overall functional properties of Tregs. Our focus on TNFR2 antibody candidates that show selective Treg cell binding and signaling profiles that may be developed for treatment of autoimmune diseases, such as ulcerative colitis, multiple sclerosis and vitiligo. Our first drug candidate in this program is NKTR-0165, which we believe is a unique bivalent antibody that selectively stimulates TNFR2 receptor activity, and we began Investigational New Drug (IND) enabling studies for NKTR-0165 in 2024. We are also designing a pipeline of bispecific molecules that pair TNFR2 agonism with other antibody targets and we have identified the first bispecific antibody, NKTR-0166, in this program. This first bispecific antibody incorporates the TNFR2 epitope with another validated antibody target, and we are initiating our preclinical studies.

In oncology, we focus on developing medicines that target biological pathways that stimulate and sustain the body's immune response in order to fight cancer. Our drug candidate NKTR-255 is an investigational biologic that is designed to target the IL-15 pathway in order to activate the body's innate and adaptive immunity. Through optimal engagement of the IL-15

receptor complex, NKTR-255 is designed to enhance functional NK cell populations and formation of long-term immunological memory, which may lead to sustained and durable anti-tumor immune response. We are continuing select developmental studies of NKTR-255 in combination with cell therapies and checkpoint inhibitors while we evaluate additional strategic partnership pathways for the program.

In December 2024, we announced the results of our Phase 2 proof-of-concept study to evaluate NKTR-255 following Yescarta®or Breyanzi®CD19 CAR-T cell therapy in patients with large B-cell lymphoma at the 66th ASH Annual Meeting and Exposition in San Diego, California. In the fifteen-person clinical trial, the NKTR-255 combined treatment group demonstrated an improved complete response rate (CRR) at six months, achieving 73% compared to 50% for the placebo, as assessed by a blinded independent central radiology review. Additionally, two patients treated with NKTR-255 converted from stable disease or partial response to complete responses at six months. No conversions from stable disease or partial response to complete response were observed in the placebo arm of the trial. The Fred Hutchinson Cancer Center is evaluating NKTR-255 following Breyanzi®CD19 CAR-T cell therapy in patients with relapsed/refractory large B-cell lymphoma as an investigator sponsored study. We are continuing our oncology clinical collaboration with Merck KGaA to evaluate the maintenance regimen of NKTR-255 in combination with avelumab, a PD-L1 inhibitor, in patients with locally advanced or metastatic urothelial carcinoma in the Phase II JAVELIN Bladder Medley study. We entered into a clinical study collaboration with AbelZeta Pharma, Inc. (AbelZeta) (formerly known as CBMG Holdings) to study NKTR-255 in combination with its C-TIL051, a tumor-infiltrating lymphocyte (TIL) therapy, in advanced non-small cell lung cancer (NSCLC) patients that are relapsed or refractory to anti-PD-1 therapy. Under the collaboration, we will contribute NKTR-255, and AbelZeta will add NKTR-255 to its ongoing AbelZeta-sponsored Phase 1 clinical trial. We also have an ongoing investigator sponsored study evaluating NKTR-255 in combination with IMFINZI (durvalumab) in patients with unresectable Stage 3 NSCLC who have received chemoradiation.

We have historically derived substantially all of our revenue and significant amounts of research and development operating capital from our collaboration agreements. We have received upfront and milestone payments and cost-sharing reimbursements under a number of previous collaboration agreements, and certain of our collaboration partners have borne substantial costs of developing our drug candidates. We expect we will continue our approach of entering into revenue-generating collaboration agreements to pay in whole or in part the development costs of our drug candidates.

Several of our historical collaboration agreements have resulted in approved drugs, for which we may be entitled to royalties for net sales of these approved drugs. However, we have sold our rights to receive royalties under these arrangements, including:

We continued to manufacture the polymer reagents used in the production of some of the drug products until the sale of our manufacturing facility in Huntsville, Alabama (the Facility) in December 2024. On December 2, 2024, we completed the sale of the Facility and assigned our manufacturing and supply agreements to Gannet BioChem, an affiliate of Ampersand Management LLC d/b/a Ampersand Capital Partners (Ampersand) for consideration of $64.7 million in cash, net of transaction costs, and an approximate 20% equity interest at the time of close in Gannet BioChem. See Note 4 to our Condensed Consolidated

Financial Statements for additional information. The sale of the Facility does not alter the royalties or other milestones payable under these agreements or our collaboration agreement with UCB for dapirolizumab pegol as further disclosed in Note 7 to our Condensed Consolidated Financial Statements.

Our business is subject to significant risks, including the risks inherent in our development efforts, the results of our clinical trials, our dependence on the marketing efforts by our collaboration partners, uncertainties associated with obtaining and enforcing patents, the lengthy and expensive regulatory approval process and competition from other products. Drug research and development is an inherently uncertain process with a high risk of failure at every stage prior to approval. The timing and outcome of clinical trial results are extremely difficult to predict. Clinical development successes and failures can have a disproportionately positive or negative impact on our scientific and medical prospects, financial condition and prospects, results of operations and market opportunities. For a discussion of these and some of the other key risks and uncertainties affecting our business, see Item 1A "Risk Factors."

With respect to financing our near-term business needs, as set forth below in "Key Developments and Trends in Liquidity and Capital Resources," we estimate we have working capital to fund our current business plans through at least the next twelve months. At September 30, 2025, we had approximately $270.2 million in cash and investments in marketable securities.

On July 2, 2025, we completed the sale and issuance of 4,893,618 shares of our common stock in an underwritten public offering (the 2025 Offering) at a price of $23.50 per share. The net proceeds to the Company from the 2025 Offering totaled approximately $107.2 million, after deducting underwriting discounts, commissions and offering costs.

We previously entered into an equity distribution agreement (the ATM Sales Agreement) with Piper Sandler & Co. and BTIG, LLC to sell shares of our common stock by any method permitted that is deemed to be an "at-the-market" equity offering as defined in Rule 415(a)(4) promulgated under the Securities Act. During the three months ended September 30, 2025, we issued 600,198 shares of our common stock under the ATM Sales Agreement at a weighted average price of $59.24 per share for net proceeds of $34.3 million after deducting related commissions and offering costs. In October 2025, we issued an additional 673,725 shares of our common stock under the ATM Sales Agreement at a weighted average price of $58.55 for net proceeds of $38.3 million after deducting related commissions. No ATM shares remain available for issuance under the ATM Sales Agreement.

See Note 6 to our Condensed Consolidated Financial Statements for additional information.

Results of Operations

The following sets forth our Condensed Consolidated Statements of Operations data for each of the periods indicated (in thousands, except percentages).

Revenue

Our revenue has historically been derived from our collaboration agreements, under which we may receive product sales revenue, royalties, and license fees, as well as development and sales milestones and other contingent payments. We recognize revenue when we transfer promised goods or services to our collaboration partners.

On March 4, 2024, Nektar and HCR amended the 2020 Purchase and Sale Agreement to remove the cap on the royalties in exchange for a $15.0 million payment to Nektar. See Note 3 to our Condensed Consolidated Financial Statements for additional information.

Research and Development Expense

Research and development expense consists primarily of direct third party costs for each of our drug candidates (including clinical study costs; contract manufacturing costs and other materials and supplies; direct costs of outside clinical, regulatory, preclinical and research services; licenses; and other fees), personnel costs (including salaries, benefits, non-cash stock-based compensation costs, and costs for consultants and temporary workers), and certain overhead support allocations.

Research and development expense decreased for the three and nine months ended September 30, 2025 as compared to the three and nine months ended September 30, 2024, respectively, as reported in the following table, which presents expenses incurred for direct third party costs for each of our drug candidates; personnel, overhead and other direct costs, as we utilize our employee and infrastructure resources across our development and research programs; and non-cash stock-based compensation and depreciation (in thousands):

Research and development expense for rezpegaldesleukin increased for the nine months ended September 30, 2025 as compared to the nine months ended September 30, 2024, due to the increase in the patients enrolled and sites activated for our Phase 2b studies in patients with moderate-to-severe atopic dermatitis and in patients with severe-to-very severe alopecia areata, both of which completed enrollment in the three months ended March 31, 2025. This increase was partially offset by lower levels of manufacturing activities. Research and development expense for rezpegaldesleukin decreased for the three months ended September 30, 2025 as compared to the three months ended September 30, 2024, due to lower levels of manufacturing activities and a decrease in expense for our Phase 2b atopic dermatitis study as patients entered the maintenance phase. As a result of the data from our Phase 2b RESOLVE-AD trial, we expect research and development expense for rezpegaldesleukin for full year 2025 to increase as compared to 2024, as we commence certain activities to support a Phase 3 trial for this program.

Research and development expense for NKTR-0165 increased for the nine months ended September 30, 2025 as compared to the nine months ended September 30, 2024, as we are conducting IND enabling activities for this program. We expect development expense for NKTR-0165 for the full year 2025 to increase slightly as compared to the full year 2024 for this same reason. In December 2023, we exercised an option to gain an exclusive license to specified agonistic antibodies and other materials that were developed pursuant to a research collaboration and license option agreement we entered into with Biolojic Design, Ltd. (Biolojic) in 2021. As we continue development of NKTR-0165, we may owe additional milestone payments to Biolojic. See Note 7 to our Condensed Consolidated Financial Statements for additional information.

Research and development expense for NKTR-255 decreased for the three and nine months ended September 30, 2025 as compared to the three and nine months ended September 30, 2024, respectively, as we have completed our Phase 2 study to

evaluate NKTR-255 following Yescarta®or Breyanzi®CD19 CAR-T cell therapy in patients with large B-cell lymphoma, and we expect development expense for NKTR-255 for full year 2025 to decrease as compared to 2024 for this same reason. Our development expense for NKTR-255 for the periods presented include our oncology clinical collaboration with Merck KGaA to evaluate the maintenance regimen of NKTR-255 in combination with avelumab, a PD-L1 inhibitor, in patients with locally advanced or metastatic urothelial carcinoma in the Phase II JAVELIN Bladder Medley study, and investigator-sponsored studies, one evaluating NKTR-255 following Breyanzi®CD19 CAR-T cell therapy in patients with relapsed/refractory large B-cell lymphoma and one evaluating NKTR-255 in combination with IMFINZI (durvalumab) in patients with unresectable Stage 3 NSCLC who have received chemoradiation.

Personnel, overhead and other costs increased for the three and nine months ended September 30, 2025 as compared to the three and nine months ended September 30, 2024, respectively, for increased personnel costs to support our rezpegaldesleukin program and increases in allocations of overhead costs to research and development expense as we no longer allocate such costs to costs of goods sold, following the sale of the Facility, and we expect these costs for full year 2025 to increase as compared to 2024 for these same reasons. Stock-based compensation expense decreased for the periods presented due to lower valuations on more recent grants as a result of a decrease in our stock price.

We expect research and development expense in total for full year 2025 to increase slightly as compared to 2024, as we commence certain activities to support a Phase 3 trial for rezpegaldesleukin, continue development of NKTR-0165 and initiate research activities for NKTR-0166.

The timing and amount of our future clinical trial expenses will vary significantly based upon our evaluation of ongoing clinical results and the structure, timing, and scope of additional clinical development programs and potential clinical collaboration partnerships (if any) for these programs.

In addition to our drug candidates that we plan to evaluate in clinical development during 2025 and beyond, we believe it is vitally important to continue our investment in a pipeline of new drug candidates to continue to build the value of our drug candidate pipeline and our business. We continue our interest in identifying new drug candidates across a wide range of molecule classes, including small molecules and large proteins, peptides and antibodies, across multiple therapeutic areas. We also plan from time to time to evaluate opportunities to in-license potential drug candidates from third parties to add to our drug discovery and development pipeline. We plan to continue to advance our most promising early research drug candidates into preclinical development with the objective to advance these early-stage research programs to human clinical studies over the next several years.

Our expenditures on current and future preclinical and clinical development programs are subject to numerous uncertainties in timing and cost to completion. In order to advance our drug candidates through clinical development, each drug candidate must be tested in numerous preclinical safety, toxicology and efficacy studies. We then conduct clinical studies for our drug candidates that take several years to complete. The cost and time required to complete clinical trials may vary significantly over the life of a clinical development program as a result of a variety of factors, including but not limited to:

Furthermore, our strategy includes the potential of entering into collaborations with third parties to participate in the development and commercialization of some of our drug candidates, or clinical collaborations where we would share costs and operational responsibility with a partner. In certain situations, the clinical development program and process for a drug candidate and the estimated completion date will largely be under the control of that third party and not under our control. We cannot forecast with any degree of certainty which of our drug candidates will be subject to future collaborations or how such arrangements would affect our development plans or capital requirements.

General and Administrative Expense

General and administrative expense includes the cost of administrative staffing, finance and legal activities, including certain overhead support allocations. Additionally, general and administrative expense includes our lease and other facilities expenses, net of sublease income.

General and administrative expense decreased for the three and nine months ended September 30, 2025 as compared to the three and nine months ended September 30, 2024, respectively. For the periods presented, facilities expense decreased primarily due to the impairment charges we recorded in 2024, resulting in decreased lease expense following the impairment, and stock-based compensation expense decreased due to lower valuations on more recent grants due to the decrease in our stock price. Legal expenses increased for the nine months ended September 30, 2025 as compared to the nine months ended September 30, 2024.

We expect general and administrative expense for full year 2025 to be comparable to full year 2024.

Restructuring and Impairment

In connection with our restructuring plans, we reported the following costs in restructuring and impairment as further described and disclosed in Note 8 to our Condensed Consolidated Financial Statements (in thousands):

Interest Income

Interest income decreased for the three and nine months ended September 30, 2025 as compared to the three and nine months ended September 30, 2024, respectively, primarily due to lower investment balances as we have utilized our investment balances to fund operations. We expect interest income to decrease for 2025 due to lower interest rates.

Loss from Equity Method Investment

As discussed in Note 4 to our Condensed Consolidated Financial Statements, we determine our gain or loss on our equity method investment in Gannet BioChem using the hypothetical liquidation at book value (HLBV) due to Ampersand's priority liquidation preference and right to receive a cumulative preferred dividend. The HLBV method is a balance sheet approach that calculates the change in the hypothetical amount we and Ampersand would be entitled to receive if Gannet BioChem were liquidated at book value at the end of each period, subject to certain adjustments for any contributions, distributions and basis differences. We report our gain or loss from our equity method investment in Gannet Biochem on a three-month lag. Therefore, our loss recorded for the three months ended September 30, 2025, reflects Gannet BioChem's activities for the three months ended June 30, 2025, and our loss recorded for the nine months ended September 30, 2025, reflects Gannet BioChem's activities from closing on December 2, 2024 through June 30, 2025. Our losses for these periods reflect Ampersand's cumulative preferred dividend earned for such periods and Gannet BioChem's net losses for such periods. Our loss of $7.4 million for the nine months ended September 30, 2025 includes $2.5 million of Ampersand's transaction costs deducted from Ampersand's cash investment in Gannet BioChem.

Liquidity and Capital Resources

We have financed our operations primarily through revenue from upfront and milestone payments under our strategic collaboration agreements, royalties and product sales, as well as public and private placements of debt and equity securities. As of September 30, 2025, we had approximately $270.2 million in cash and investments in marketable securities.

During 2024, we entered into the following transactions:

We filed a shelf registration statement on Form S-3 and a related prospectus (the Shelf Registration Statement) that was declared effective by the Securities and Exchange Commission (the SEC) on April 1, 2025. Pursuant to the Shelf Registration Statement, we may offer and sell common stock, preferred stock, debt securities, warrants and or units having an aggregate public offering price of up to $300.0 million. In connection with the filing of the Shelf Registration Statement, we also entered into an equity distribution agreement (the ATM Sales Agreement) with Piper Sandler & Co. and BTIG, LLC, relating to the sale of our common stock having an aggregate offering price of up to $75.0 million (the ATM Shares). The sales of the ATM Shares will be made by any method permitted that is deemed to be an "at-the-market" equity offering as defined in Rule 415(a)(4) promulgated under the Securities Act, including sales made directly on or through Nasdaq or on any other existing trading market for our common stock. We have agreed to pay Piper Sandler & Co. and BTIG, LLC a commission equal to 3.0% of the gross sales price of all common stock sold through them as sales agents.

On July 2, 2025, pursuant to the Shelf Registration Statement, we completed the sale and issuance of 4,893,618 shares of our common stock in an underwritten public offering (the 2025 Offering) at a price of $23.50 per share. The net proceeds to the Company from the 2025 Offering totaled approximately $107.2 million, after deducting underwriting discounts, commissions and offering costs. See Note 6 to our Condensed Consolidated Financial Statements for additional information.

In September and October 2025, we issued 1,273,923 shares of our common stock under the ATM Sales Agreement at a weighted average price of $58.87 per share for net proceeds of $72.5 million after deducting related commissions and offering costs of approximately $2.5 million. No ATM shares remain available for issuance under the ATM Sales Agreement.

We estimate that we have working capital to fund our current business plans for at least the next twelve months from the date of filing.

We expect the clinical development of our drug candidates, including rezpegaldesleukin, NKTR-255, NKTR-0165, and NKTR-0166 will continue to require significant investment to continue to advance in clinical development with the objective of obtaining regulatory approval or entering into one or more collaboration partnerships. In the past, we have received a number of significant payments from collaboration agreements and other significant transactions, including $1.9 billion in total consideration received under our arrangement with Bristol-Myers Squibb Company (BMS), development cost reimbursements from BMS, and a $150.0 million upfront payment from Eli Lilly and Company for our collaboration agreement for rezpegaldesleukin. Additionally, certain of our collaboration partners have borne substantial costs of developing our drug candidates. We expect we will continue our approach of entering into revenue-generating collaboration agreements to pay in whole or in part the development costs of our drug candidates.

Our current business is subject to significant uncertainties and risks as a result of, among other factors, clinical and regulatory outcomes for rezpegaldesleukin, NKTR-255, NKTR-0165 and NKTR-0166; the sales levels for those products, if and when they are approved; whether, when and on what terms we are able to enter into new collaboration transactions; expenses being higher than anticipated, unplanned expenses and the need to satisfy contingent liabilities, including litigation matters and indemnification obligations; and cash receipts, including sublease income, being lower than anticipated.

We have no credit facility or any other sources of committed capital. The availability and terms of various financing alternatives, if required in the future, substantially depend on many factors including the success or failure of drug development programs in our pipeline. The availability and terms of financing alternatives and any future significant payments from existing or new collaborations depend on the positive outcome of ongoing or planned clinical studies, whether we or our partners are successful in obtaining regulatory authority approvals in major markets, and if approved, the commercial success of these drugs, as well as general capital market conditions. We may pursue various financing alternatives to fund the expansion of our business as appropriate.

As a result of our restructuring plans, we are seeking to sublease all of our laboratory and office space in the Mission Bay Facility and our office space in the Third St. Facility, and we have current subleases for a portion of the Mission Bay Facility. The San Francisco Bay Area office lease market has been negatively impacted by economic uncertainties, particularly impacting the

technology industry, and the change in work habits, as employees continue to work remotely. Accordingly, for the Third St. Facility, there is significant uncertainty as to whether or when we will be able to enter into a sublease as well as the economic terms of such subleases, if any. Meanwhile, the San Francisco Bay Area life sciences lease market continues to be weak as a significant amount of leasable space remains available in the San Francisco Bay Area. Accordingly, there is uncertainty as to whether or when we will be able to enter into a sublease as well as the economic terms of such subleases, if any.

Due to the potential for adverse developments in the credit markets, we may experience reduced liquidity with respect to some of our investments in marketable securities. These investments are generally held to maturity, which, in accordance with our investment policy, is less than two years. However, if the need arises to liquidate such securities before maturity, we may experience losses on liquidation. To date we have not experienced any liquidity issues with respect to these securities. We believe that, even allowing for potential liquidity issues with respect to these securities and the effect of various conditions on the financial markets, our remaining cash and investments in marketable securities will be sufficient to meet our anticipated cash needs for at least the next twelve months.

Cash flows from operating activities

Cash flows used in operating activities for the nine months ended September 30, 2025 and 2024 totaled $143.6 million and $129.5 million, respectively.

We expect that cash flows used in operating activities, excluding upfront, milestone and other contingent payments received, if any, will increase for 2025 as compared to 2024.

Cash flows from investing activities

During the nine months ended September 30, 2025, we purchased $0.7 million investments, net of maturities as we have invested the proceeds from our equity financings, offset by funding our operations. During the nine months ended September 30, 2024, the maturities of our investments, net of purchases, totaled $83.4 million, which we used to fund our operations. Our other investing activities were not significant for the periods presented.

Cash flows from financing activities

Other than the financing activities described above, our cash flows from financing activities for the nine months ended September 30, 2025 and 2024 were not significant.

Critical Accounting Policies and Estimates

The preparation and presentation of financial statements in conformity with U.S. generally accepted accounting principles (GAAP) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period.

We base our estimates on historical experience and on various other assumptions that we believe to be reasonable under the circumstances, the results of which form our basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. We evaluate our estimates on an ongoing basis. Actual results may differ from those estimates under different assumptions or conditions.

Other than our policy for our gain or loss on equity method investment as discussed in Notes 1 and 4 to our Condensed Consolidated Financial Statements, there have been no material changes to our critical accounting policies and estimates discussed in our Annual Report on Form 10-K for the fiscal year ended December 31, 2024.